Problem: Evaluate the following expression when $x = 5$ and $y = 1$. $7$ $x$ $^2 + 9$ $y$ $ - 9$
Answer: Substitute $5$ for ${x}$ and $1$ for ${y}$ $ = 7{(5)}^2 + 9{(1)} - 9 $ Remember order of operations. Evaluate the exponent before you multiply. $ = 7(25) + 9{(1)} - 9 $ $ = 175 + 9 - 9 $ $ = 175$